254nm? interesting for visible or uv light, which wavelength?
22497
Didn't last 60 days, company wouldn't do anything about their product! Would not recommend!!!!
22498
254 nm (nanometers) is in the ultraviolet part of the spectrum. Exposure to it will kill bacteria and viruses; it will damage one's eyes.
2103642
http://imaginatorium.org/stuff/tubes.htmif you increase the iso that means that you need less stops of light. so a 400 iso is more sensitive to light than 200 by double, and 200 is double sensitive than 100 iso. so hope this helps. please check the page where the calculations are made.
1943334
There is no UV light emitted by the product. UV light starts at 400nm and below, whereas the product puts out light from the 590nm to 880nm range, well above the UV spectrum. Goggles are included with the product and MUST be used at all times, since the light is very bright.
2041486
It can see in less light than my eyes can, so I say yes. I don't know what wavelength illuminator you would need to brighten the picture, but near-infrared should work.
1472268
Hello Mark, Near IR is 700nm to 1400nm. Generally used for heat therapy. Intense heat. Very hazardous to the eye. The standard R and BR shaped heat lamps we sell (like the 55964 on Amazon) are Far IR. Very different. Thank you, Victoria Supply
968368
Based on my experience, if a system won't detect at 850, then it won't at 940. Cameras and cell phones must have night-vision capability or infrared sensors in order to detect light beyond 850nm. Expensive night googles should be able to see in the IR wavelength, but a search to make sure your devices are capable of the 940nm range is recommended. 940 is often more desirable because it gives off very little visible light and is therefore extremely hard to detect.
1043030
It is VERY noticeable, I have a 2700K and a 2100K right next to each other and the 2100K has more blue added to the spectrum, the visible light is somewhat purple whereas the 2700K is very red. The 2100K is marked "for veg and flower" I've never tried using it by itself but I imagine it would make a suitable light if you could only afford to get one bulb, it's not ideal for veg but it'll work and it's great for flower.
2079708
5 vs. 4 wavelength backlight means better color reproduction. 120hz refresh rate means less judder/smoother motion on fast moving action scenes. 15,000 vs. 10,000 Dynamic contrast ratio means deeper blacks (ie, see more picture detail in dark areas of image). I think those are the main differences and justify the higher selling price (but perhaps not to the tune of $1,000-$2,000....$500 difference would be more realistic)
2216340
For n=5, mean(STD) in mA: IR = 133(5), IG = 32(0.7), and IB = 25(4) @ 3.33V, 70F.If you are targeting some specific spectrum range, then anode current limiting or resistors may be needed for calibration. If you don't care a lot, then a 1K ohm at the cathode would likely do.
1049050
I'd go with a much stronger filter. 1.8 maybe. Don't stack you'll just be begging for light scatter shooting in to a light source like that.
1356478
I don't know if it's exactly 850 nm. If you look directly at the light (LEDs) at night, you can see that the lights are red (not blue). It does not add any light to the surrounding area, but the light itself can be seen from quite a distance (although very dim, I can see it from 20-30 feet away) if you look right at it. However, it does not shine any visible light into my daughter's bedroom, which was my main concern. My security camera (Archerfish Solo, now called CheckVideo Solo, is non-IR) is now able to see everything at night with the use of this light.
2123821
I have a 395nm Flashlight from Cybertech with 9 UV LEDS (Its a 3 in one with a reg flashlight, red laser and UV ) it will detect dry stains, but not wet ones. There is a good bit of purple haze at 395 though it works. 365-375 shows awesome, and I am waiting to test and make a comparison with a 380-385 one
1709903
UV-B is the UV you need to worry about, but it's in the 280nm - 315nm range. UV-A is essentially what's known as blacklight, in the 315nm - 400nm range. Starting at 400nm, we get violet, of the visible and non-ultra kind. So this 395nm light is at the safe end of blacklight. No need to worry. It's OK for lighting up phosphorescent material, but not even close to the kind of UV you get at the tanning salon.
682108
Yes you will see vignetting near the 24mm range and maybe in the 30mm range. If you use the polarizing filter take off the UV filter first. You do not need both on and the more you stack the worse the vignetting will get.
1243596
does contrast ratio make a lot of difference? I'm also debating btwn 4061 and 4065.
1029266
This flashlight puts out near UVA light, at about 400 nm. Humans can see down to 385 nm. Bright Sunlight has more radiation at this wavelength than this flashlight so our eyes get exposed to this level of near UV light for hours at a time if you don't wear sunglasses. UVA is hardly filtered by the ozone layer so almost all UVA reaches us and this flashlight produces light at the very edge of UVA and visible light.People fear UV but it is the deep UV that harms you. Turn the light on and put it on your arm. Do you get sunburn that is caused by UV? No way. Put your arm under a DEEP UV light and it will cause redness. Just use a regular pair of sunglasses if you want but it is unnecessary. This flashlight puts out near UVA light, at about 400 nm. Humans can see down to 385 nm. Bright Sunlight has more radiation at this wavelength than this flashlight so our eyes get exposed to this level of near UV light for hours at a time if you don't wear sunglasses. UVA is hardly filtered by the ozone layer so almost all UVA reaches us and this flashlight produces light at the very edge of UVA and visible light.People fear UV but it is the deep UV that harms you. Turn the light on and put it on your arm. Do you get sunburn that is caused by UV? No way. Put your arm... » Read More This flashlight puts out near UVA light, at about 400 nm. Humans can see down to 385 nm. Bright Sunlight has more radiation at this wavelength than this flashlight so our eyes get exposed to this level of near UV light for hours at a time if you don't wear sunglasses. UVA is hardly filtered by the ozone layer so almost all UVA reaches us and this flashlight produces light at the very edge of UVA and visible light.People fear UV but it is the deep UV that harms you. Turn the light on and put it on your arm. Do you get sunburn that is caused by UV? No way. Put your arm under a DEEP UV light and it will cause redness. Just use a regular pair of sunglasses if you want but it is unnecessary. « Show Less
153328
Wavelength seems to be in the (most common) near-IR range of 850nm. Personally, I like the 950nm ones better, but they are harder to find and more expensive. I do find this model to be very bright (when viewing through camera) though I can't say for certain what its range is as I only use it out to 25ft.